<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .text{
            color: red;
        }
        .content{
            font: 100px;
        }

        
    </style>
</head>
<body>
    <p class="text content" >你好</p>
    <h3 class="text">hello</h3>
    <h3>hello</h3>

</body>
</html>